The research proposed herein consists of designing various surgical procedures for cervical spinal stabilization following trauma, and testing them on a canine experimental model. A testing apparatus utilized previously to study the biomechanics of the flexion failure of canine cervical spine segments will be modified in the following 2 ways: 1. It will be interfaced with a microcomputer. 2. To allow immediate print out of biomechanical data (Angular Deformation Stiffness, Horizontal Translation Stiffness, Ultimate Force and Ultimate Moment). The research will then procede along two basic lines. In the first, cadaveric canine cervival spinal segments will be flexed to biomechanical failure via the above apparatus producing a model analogous to the human cervical facet dislocation. Various simulated surgical repair procedures will then be performed on this model. The repaired specimens will again be flexed to biomechanical failure. In this way the Immediate Stability of the various repairs will be studied. In the second, various posterior cervical spine fusion procedures will be performed on living canines. The fusions will be allowed to mature within the living animals for 1, 2 or 3 months prior to harvesting. Following sacrifice and harvesting, the fused cervical spine specimens will again be biomechanically studied during flexion failure. In this way biomechanical maturation of various spinal fusion procedures will be studied.